Fuse-block.



R. G. COLE.

FUSE BLOGK.

APPLIOATION FILED Emma, 1912.

Patented Ju1y9, 1912.

2 SHEETS-EEEET 1.

ROBERT CHAS. COLE, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE JOHNS-IRATE COMPANY, OF HARTFORIO, CONNECTICUT, CORPORATION OF CONNECTICUT.

F SE-moon.

Specification of Letters Iatent.

Application filed March 23, 1912. Serial No. 685,820.

Patented July 9, 1912.

' To all whom. it may concern.

' Hartford, in the county of Hartford and State of Connecticut,- have invented a new and useful Improvement in. Fuse-Blocks, of which the following is a specification.

This invention relates to the arrangement of a fuse block which is particularly designed to be used in connection with an electric meter.

The object of the invention is to provide a very simple, cheap and compact block, which is so arranged that connections between the service or main line circuit wires and a meter, and between the meter and the load or branch line circuitwires can be easily and quickly made in such manner that the meter will be protected on both sides by fuses, and, whenever it is desired .to test the meter, the fuses can be quickly manipulated or changed from one position to another and testing instruments can be readily connected and the test made without interfering with the load circuit or customers current, and without eliminating the protection afforded to the circuits and to the meter and testing instruments by the fuses.

Figure 1 of the accompanying drawings is a view looking at the top edge of a meter connecting fuse block which embodies the invention. Fig. 2 shows a plan of the block. Fig. 3 is a view looking at the bottom edge of the block. Fig. 4 is a side view of an instrument connecting handle that may be used with this block. Fig. 5 is a conventional diagram indicating the electrical connections when this block is used in a two-wire system with the circuits in normal condition, that is, with the circuits arranged for regular service. Fig.6 is diagram indicating the same circuits as they would be connected when a test was to be made. Fig. 7 is a diagram indicating the circuits when the block was to be used in a three-wire system, arranged in normal service condition. 2

The base 1 of the block is desirably made of porcelain, although it may be made of slate, molded compound, or any other suitable insulating material. 7

Contact plates 2, 3, 4, 5 are fastened to the face of the base near one edge. These plates are provided with binding screws for the connection of the wires to and from the meter, and they are shown as having outwardly projecting stud heads 6, 7, 8, 9. Electrically connected, longitudinally, to these contact plates are fuse clips 10, 11, 12,13. Contact plates 14,15, 16, 17 are fastened to the face of the base near the other edge. These contact plates have binding screws 18, '19, 20, 21 for the connection of the and or feed andreturn, or outside wires, of the service and load circuits. The device is used with both direct current and with alternating current systems, but for convenience of description the service and load wires which are on one side of the circuit are hereafter termed feed wires, and those on the other side are termed return wires, whether they refer to direct or alternating current circuits. Electrically connected, longitudinally, to these contact plates are fuse clips 22, 23, 24, 25. Electrically connected, transv'ersely, to these contact plates are fuse clips 26, 27, 28, 29. If the block is to be used in a two-wire system, these are all the fixed parts that are necessary to carry out the invention. If it is desired to use the block in a three-wire system, a contactplate 30 with a binding screw for the connection of the neutral meter lead, and a fuse clip 31 may be provided near one edge, and a cons tact plate 32 with a binding screw for the connect-ion of the neutral service wire, and,

used in a three-wire system a fuse 38 may be put into the clips 31 and 33. 3

. The positive, or feed, or outside line or service wire may be connected with the contact plate 14, and the negative, return, or other outside line or service wire may be connected with the contact plate 17. The positive, feed, or outside wire of the load circuit may be connected with the contact 15 and the ,negative, return or other outside wire 'of the load circuit may be connected with the contact 16, as indicated by the diagrams- The ampere coil or coils 39 of the meter M may be connected with the contacts 2 and 3, and one end of the potential coil 40 of the meter may be connected with the contacts 4 and 5, as indicated in Fig. 5. If the connections are made in this manner,the positive, or feed side of the main or service circuit is connected with the positive, or feed side of the load circuit through the contact 14, fuse 34, contact 2, meter, cont-act 3, fuse 35, and contact 15. The negative or return wires of the load and service circuits are connected through-the contact 16, fuse 36, contact 4, meter, contact 5, fuse 37, and contact 17. With such connections and the fuses arranged as shown in Figs. 2 and 5 of the drawings, the circuits are in condition for normal use, and there is a fuse on each side of the circuit on both sides of the meter. Thus the meter is protected from excess currents occuring from overloads or short circuits or grounds, either on thevload or main lines. When it is desired to test a meter connected and protected in this way, the

fuse 35 may be removed from the clips 11.

and 23, and the fuse 36 may be removed from the clips 12 and 24, thus disconnecting the contacts 3 and 15 and the contacts 4 and 16. These fuses may then be placed, one between the clips 26 and 27, and the other between the cllps 28 and 29, so as to connect the contacts 14 and 15 and the con-' tacts 16 and 17.

It is desirable in practice to connect the clips 26 and 27 and the clips 28 and 29 with fuses before removing the fuses 35 and 36, for by doing this there is no danger of drawing an arc when the fuses 35 and 36 are pulled out. With the fuses 35 and 36 removed from the clips. 11, 23 and 12, 24, and placed in the clips 26, 27 and 28, 29, the contacts 14 and v15, which were before disconnected are now connected, and the 3 contacts 3 and 15, which were before connected are now disconnected, and the contacts 16 and '17, which were before disconnected are now connected, and the contacts 4 and 16 which were before connected are now disconnected. Arranging the fuses in this way bridges both sides of the. line and practically short-circuits the meter without however leaving either the meter or the load lines unprotected by fuses, as indicated in Fig. 6. When the fuses are in this relation, connecting one side of a voltmeter V with the contact 2 and the other side with the contact 5, puts the voltmeter across the main lines. Connecting one terminal of a portable standard, or ammeter A and variable resistance with the contact 3 and connecting the other terminal of such an instrument with the contact 4 puts the testing instrument in .series with the meter as indicated in Fig. 6, the connections between the meter and the block being shown in- Fig. 5. In this case the load circuit is not interrupted, but the volt meter is connected across the line, and the portable standard, or ammeter and variable resistance, or artificial load, is connected in series with the meter, in a circuit that is in shunt with the service and load wires as now connected. This is but an illustrative connection, and is one in which current from the main source of'supply is utilized to make the test.

strument connections quickly a terminal handle 41 may be provided. This handle may have in one edge a number of conducting sockets 42 connected with the proper lead wires for the testing'instruments. To connect the instruments with the circuits for testing purposes, by one act the metallic terminal sockets in the handle are thrust upon the binding screw studs 6, 7, 8, 9. It is desirable to provide this handle with ribs 43 on its sides so that the sockets-cannot be thrust upon the studs for connecting the testing instruments until after the fuses 35 and 37 have been removed, and the meter lines opened. When the testing instruments are connected in this manner, the potential of the line may be read and the meter may be tested and compared without in any way interfering with the load lines or the current supplied to a customer, for the meter and the measuring instruments with which the meter is in series are connected in multiple with the load.

When it is desired to use the block with a three-wire system, and provide a meter tap for the neutral wire, the contacts 30 and 32 are fastened to the base and a fuse 38 inserted into the clips 31 and 33 connected with these contacts. Then the neutral wire may be connected with one contact, and taken from the other, as indicated by Fig. 7. For testing under these conditions the .in-

struments are connected the same as above fuses can be easily and quickly manipulated to change the circuits from normal service to testing conditions. When the fusesare" arranged as in normal use, both lines are fused each side of the meter, and when the means fuses are arranged for testing, both sides of the circuit between the service and the'load lines are fused,and also both sides of the circuit through the meter and through the testing instruments are fused.

The invention claimed is:

1. A meter connection fuse block having contacts for service wires, load wires, and meter leads, the contacts for the feed side of the service and load wires being adjacent to each other at one end of the block and the contacts for the return side of the service and load wires being adjacent to each other at the same end, means for fusibly connecting the service wire and load wire contacts with the meter lead contacts, and means for fusibly connecting the adjacent service wire and load wire feed side contacts and for fusibly connecting the adjacent service wire and load wire return sidecontacts and thus short circuiting the meter .lead' contacts.

2. A meter connection fuse block having contacts for service wires, load wires, and meter leads, the contacts for the feed side of the service and load wires being adjacent to each other at one endof the block and the contacts for the return side of the service and load wires being adjacent to each other at the same end, fuse clips connected with said contacts, fuses connecting said service wire and load wire contact clips with said meter lead contact clips, and fuse clips connected with said service wire and load wire contacts, said last mentioned clips being spaced between the adjacent feed wire contacts and being spaced between the adjacent return wire contacts the same distance apart as are the first ment-ionedclips whereby said last mentioned clips will take the same fuses as the first mentioned clips for fusibly connecting and providing a direct path for electric current from the service wire contacts to the load wire contacts.

3. A meter connection fuse block having contacts for service wires, load wires, and meter leads, similar fuse terminals connected with the several contacts, each of the meter lead contacts having a single fuse terminal and each of the service and load wire contacts havingtwo fuse terminals, and fuses connecting the service and load contact fuse terminals with the meter lead fuse terminals in series, a part of said fuses being removable from the series connections and replaceable across the contacts so as to connect the same sides of the service and load wires with each other.

4:. A meter connection fuse block having contacts for service wires and load wires,

two similar fuse terminals connected with each of said contacts, contacts for meter leads, one fuse terminal of the same. type connected with each meter lead contact, and means for connecting testing instruments with the meter lead contacts.

ing measurin service wire contacts, load wire contacts,

meter lead contacts, one fuse terminal connected with each meter lead contact, two fuse terminals connected with each service wirecontalct, and two fuse terminals connected with each load wire contact, the said fuse terminals on the service wire contacts and on the load wire contacts being arranged so as to permit the service and load wire contacts to be fusibly connected with the meter lead contacts and also with each other.

7. A meter connection fuse block having.

tacts each provided with one spring clip, the

contacts for thefeed side of the service and load wires being adjacent to each other 'at one end of the block and the contacts for the return side of the service and load wires being adjacent to each other at the same end, and inclosed fuses adapted to fusibly connect the meter lead contact clips with the service contact clips and the meter lead contact clips with the load contact clips, or connect the same sides of the service and load contact clips together, whereby in the first instance the circuit would be through a meter and in the second instance would be di rectly to the load.

'8. A meter connection fuse block having service wire contacts, each contact having two fuse clips, load wire contacts, each having two fuse clips, meter lead contacts, each having one fuse clip and means for connector testing instrument leads, the contacts or the feed side of the service and load wires being adjacent to each other at one end of the block and the contacts for the return side of the service and load wires being adjacent to each other at the same end, and mclosed fuses connecting the fuse cli s of the service and load contacts with t e fuse clips of the meter lead contacts, said fuses between the meter lead contact cli s and the load contact clips being removab e therefrom and insertible between the service contact clips and load contact clips to connect the same sides of the circuit together,

thereby cutting out the meter lead contacts and making direct connection between the service and the load contacts.

.9. A meter connection fuse block having contacts for the connection of service wires, load wires and meter leads, the contacts for the feed side of the service and load wires being adjacent to each other at one end of the block and the contacts for the return side of the service and load wires being ad: jacent to each other at the same end, fuse terminals connected with said contacts in such manner that the service wires *and load wires may be fusibly connected with the meter leads, or the same sides of the service wires may be fusibly connected directly with the load wires by the same fusible means, and means forconnecting measuring or test ing'instruments with the meter lead contacts.

10. A meter connection fuse block having means for the connection of servioe wires zi eee iee toad wires, meter leads, end testin' instm ments, the contacts for the feed si e cf the service and load wires hein adjacent each other at one end of the %lock and the contacts for the return side of the service and load wires being adjacent to eech ethes at the same end, and fuses normally connecting said service and load connecting meens in series with the meter 'coeeting means and adapted to be shifted item said series connection to PYOdUiCG a multilie connection of the met-er." lead and load were connecting 

